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Great_White

About Projection Transform

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Great_White    148
Hi, I'm wondering sth. about the projection of 3d objects. After the projection transformation, are these vertices of 3D objects projected to the near plane or the far plane ?

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Quat    568
The perspective transformation (including the nonlinear divide by w) maps the frustum volume into the box volume [-1,1]x[-1,1]x[0,1] (Direct3D style).

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Quat    568
The far plane is part of the frustum description. Without it, your frustum would be unbounded. It is basically to clip geometry far away from the eye.

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skytiger    294
perspective transform maps the view frustum

into a rectangle with depth

each point on the rectangle maps

to everything in world space

that could be behind that pixel

ie: something small close up

or something big along way away

imagine each pixel is a window into the 3D world

like a real window one meter wide

it can show something close up to one meter wide

but a mountain range could be 10 thousand meter's wide

both visible in the same window

the Z coordinate of each pixel represents how far
from the camera that vertex is

hope that helps

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Great_White    148
Quote:
Original post by skytiger
perspective transform maps the view frustum

into a rectangle with depth

each point on the rectangle maps

to everything in world space

that could be behind that pixel

ie: something small close up

or something big along way away

imagine each pixel is a window into the 3D world

like a real window one meter wide

it can show something close up to one meter wide

but a mountain range could be 10 thousand meter's wide

both visible in the same window

the Z coordinate of each pixel represents how far
from the camera that vertex is

hope that helps


It helps, so this window is near-plane of the frustum, right?

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